Electric lamp base end structure

ABSTRACT

An electrical device with a stem press with a groove therein terminating in an end wall and having a lead wire bent around the edge of the stem press and placed in the groove so as to extend beyond the end wall to an area of the press behind the end wall. A hollow metal base fitted over the stem press has an inwardly directed tongue resiliently clamping the lead wire against the portion of the stem press behind the end wall.

waited States DeBleyker et a1.

atent [191 1 June 12, 197.3

1 ELECTRIC LAMP BASE END STRUCTURE [75] Inventors: James R. DeBleyker, Cleveland,

Ohio; William A. Hickox, Memphis, Tenn.

[73] Assignee: General Electric Company,

Schenectady, NY.

[22] Filed: Sept. 30, 1971 [21] Appl. No.: 185,119

[52] U.S. Cl. 313/318, 313/317, 339/144,

339/145 [51] Int. Cl. H0lj 5/50 [58] Field of Search 313/317, 318;

339/144 R, 144 T, 145 D, 145 T [56] References Cited UNITED STATES PATENTS 3,093,768 6/1963 Ayres 313/318 3,320,466 5/1967 Ayres et a1 313/318 3,156,841 11/1964 Ayres 313/318 X FOREIGN PATENTS OR APPLICATIONS 1,520,151 2/1968 France 313/318 1,189,791 4/1970 Great Britain 339/144 R 782,061 4/1968 Canada 313/318 Primary Examiner-Ronald L. Wibert Assistant Examiner-Paul A. Sacher Att0rney-Henry P. Truesdell, Frank L. Neuhauser,

Oscar B. Waddell et al.

[5 7] ABSTRACT An electrical device with a stem press with a groove therein terminating in an end wall and having a lead wire bent around the edge of the stem press and placed in the groove so as to extend beyond the end wall to an area of the press behind the end wall. A hollow metal base fitted over the stem press has an inwardly directed tongue resiliently clamping the lead wire against the portion of the stem press behind the end wall.

2 Claims, 6 Drawing Figures Patented June 12, 1973 3,739,221

lnven'toT-si James R. DeBLeyker WiLLiam A.l'iic:l ox

Their A t tor-neg BACKGROUND OF THE INVENTION 1. Field of the Invention DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 illustrates a conventional double-ended incan- This invention relates to electrical energy translating descent lamp having a sealed envelope 1 of vitreous devices and particularly lamps having a base fitted over a stem press to make electrical contact with the lampss lead wire.

2. Description of the Prior Art Lamps of the stem press variety are used in many fields including automotive dome, dash and tail lighting. This type of lamp is described in US. Pat. No. 3,156,841 Ayres, assigned to the same assignee as that of the present invention.

The lamp base therein described is an open metal band which requires orientation of the metal section of the band with respect to the metal or conductive portion of a socket. This orientation has caused some problems in the mass production auto industry where rapid lamp insertion is desirable.

In an attempt to alleviate these problems, a closed circular hollow metal base was preassembled over the metal base structure illustrated in Ayres US. Pat. No. 3,156,841. This solution not only required an additional assembly stem but also led to additional material costs in that two metal base components were now required.

It is, therefore, an object of the invention to eliminate the additional material and process step of the prior art by providing a lamp with an inexpensive base capable of rapid insertion.

SUMMARY OF THE INVENTION In accordance with one aspect of the invention, a stem press is made on a lamp envelope with a groove in each side of the press. The groove, by not extending the full length of the press, forms an end wall with the presss surface. Two shoulders are formed on the stem press one on each side of the groove located forward of the end wall. The extended end of the hermetically sealed lead wire, is bent around the edge of the stem press and extends through the groove over the end wall so as to overlie the press surface behind the end wall.

A base with an inwardly projecting metal tongue is snugly fitted over the stem press and resiliently clamps the lead wire against that portion of the press behind the end wall.

Bases of the invention take a generally symmetrical form so that a minimum amount of orientation is necessary to engage the socket and lead .wire. On lamps of the double-ended variety, the same base is used at each end so end-to-end orientation is not necessary. These base characteristics make for rapid base to lead wire and base to socket assembly.

BRIEF DESCRIPTION OF THE DRAWING In the drawing,

FIG. 1 is an elevation of an incandescent lamp embodying the invention;

FIG. 2 is a fragmentary perspective view of the stem press of the invention;

FIG. 3 is a fragmentary section view of the stem press and base of the invention; and

FIGS. 4, 5 and 6 are perspective views of three types of bases of the invention.

material, such as fused quartz or glass, and an incandescible filament 2. Opposite ends of the filament are connected to lead wires 3 which are hermetically sealed in stem presses 4, as shown in FIG. 2, each stem press being formed with opposite substantially flat surfaces 5 in which grooves 6 are formed. The grooves 6 extend from the outer edge of the stem press inwardly a small distance where they terminate in an end wall 7 short of the lamp envelope 1. The length of the lead wire 3 is such that it can be bent around the outer edge 8 of the stem press, and extend over end wall 7. Shoulders 9 are located on each side of the grooves to guide the bent lead wires to a clamping position 10 on the surface of the stem press behind end wall 7.

One form of base 11 is shown in FIGS. 1, 3 and 4. Base 11 is formed as a hollow cylindrical member of sheet metal, such as nickel-plated steel, with tongues 12 extending inwardly from the outer surface 13. Tongues 12 may preferably have a V-notch 14 for engaging lead wire 3.

In assembling the base 11 to the stem press, the base is positioned so that one of the tongues 12 is in alignment with the lead wire 3 and opposite tongues will frictionally engage opposite surfaces of the stem press. The base is advanced to a point where the tongues 12 pass over shoulder 9 and snap or spring into clamping position securing the lead wire against the surface of the stem press behind the end wall 7. As the base is forced onto the stern press and the tongue drags over the stem press surface, the shoulders serve to lift the tongue at the point where it passes end wall 7 to prevent the shearing of the lead wire which sometimes occurs where the wire is bent over end wall 7. Furthermore, shoulders 9 also prevent endwise removal of the base from the press.

A modified base form 15 is shown in FIG. 5. Tongues 16 of base 15 resiliently clamp the lead wire 3 of FIGS. 2 and 3. Base 15 has flat sections 17 for fitting over the stem press and is made of sheet metal crimped at 18 to generally cylindrical form. Surface 19 of base 15 is curved to fit the envelope contour. In FIG. 6, a rectangular modification of a base 20 is shown. Tongues 21 make contact with lead wire 3. Base 20 is of generally hollow rectangular shape and made from sheet metal with the edges locked by a dovetail joint, as shown at 22. Protruding from the assembled base 20 is a tab member 23 with an opening 24 for a special purpose socket. The process of fitting the base over the stem press and guiding the tongues to the clamping position is similar to that described above for base 11.

By forming a groove in opposite faces of the stem press, it is possible to bend the lead wire 3 to either side for positioning in the groove thereby facilitating orientation of the lamp for lead wire bending and base application during manufacture. Grooves 6 help control bending of the lead wire and serve to position the lead properly for engagement with the tongues on the base. Notch 14 straddles the lead wire to hold the lead in position but is of a depth such that good electrical contact is achieved between the tongue and the base.

What we claim as new and desire to secure by Letters Patent of the United States is:

1. An electric lamp comprising a sealed tubular vitreous envelope provided at its opposite ends with stem presses disposed in a common plane, each of said stem presses having a groove in one of its surfaces, said groove extending from the outer edge of said stem press inwardly toward said envelope, said groove terminating in an end wall, lead wires hermetically sealed in respective stem presses and extending into said envelope, a filament connected at its opposite ends to said lead wires, each of said lead wires extending outwardly from the respective stem presses and being bent at the outer edge of said stem press so as to be positioned in said groove and extending beyond the end wall of said groove and overlying the surface of the stem press behind said end wall, each of said stem presses containing at least one shoulder located forward of its end wall and hollow metal base members fitted over said stem presses and provided with spring-like tongues extending inwardly of the surface of said bases toward said stem presses, said tongues having a V-notch, said shoulders located in respect to said end wall such that said spring-like tongues pass over said end wall and said V- notch of said tongues resiliently clamp said lead wire against said stem press surface behind said end wall to form an electrical connection with said lead conductor.

2. The electrical device of claim 1 wherein saidhollow base member contains two spring-like tongues said tongues being positioned apart from each other. 

1. An electric lamp comprising a sealed tubular vitreous envelope provided at its opposite ends with stem presses disposed in a common plane, each of said stem presses having a groove in one of its surfaces, said groove extending from the outer edge of said stem press inwardly toward said envelope, said groove terminating in an end wall, lead wires hermetically sealed in respective stem presses and extending into said envelope, a filament connected at its opposite ends to said lead wires, each of said lead wires extending outwardly from the respective stem presses and being bent at tHe outer edge of said stem press so as to be positioned in said groove and extending beyond the end wall of said groove and overlying the surface of the stem press behind said end wall, each of said stem presses containing at least one shoulder located forward of its end wall and hollow metal base members fitted over said stem presses and provided with springlike tongues extending inwardly of the surface of said bases toward said stem presses, said tongues having a V-notch, said shoulders located in respect to said end wall such that said spring-like tongues pass over said end wall and said V-notch of said tongues resiliently clamp said lead wire against said stem press surface behind said end wall to form an electrical connection with said lead conductor.
 2. The electrical device of claim 1 wherein said hollow base member contains two spring-like tongues said tongues being positioned 180* apart from each other. 